S&W J Frame Model 642-2 Airweight Bolt, Spring & Plunger (MIM) .38 Special +P – Part# 642C

Smith & Wesson J Frame Model 642-2 Airweight Bolt, Spring & Plunger (MIM) – Stainless Steel

Restore reliable cylinder rotation and lockup on your Model 642-2 Airweight with this factory-original MIM bolt, spring, and plunger set. The bolt (cylinder stop bolt) works in conjunction with the cylinder stop to index and lock each chamber in line with the barrel at the moment of firing — a worn or damaged bolt leads to cylinder timing issues and inconsistent lockup. This MIM (Metal Injection Molded) stainless steel three-piece set is the correct factory replacement for the J Frame Model 642-2 chambered in .38 S&W Special +P.

• Part Number: 642C
• Fits: Smith & Wesson J Frame Model 642-2 Airweight
• Caliber: .38 S&W Special +P
• Includes: Bolt, Bolt Spring & Bolt Plunger
• Material: MIM (Metal Injection Molded)
• Finish: Stainless Steel
• Condition: Used (factory original)
• Installation: Gunsmith fitting recommended

About MIM Parts

Metal Injection Molding (MIM) is a precision manufacturing process used by Smith & Wesson and other major firearms manufacturers to produce complex internal components with tight tolerances and consistent quality. MIM parts are genuine factory components — not aftermarket substitutes — and meet the same specifications as traditionally machined parts.

Factory Replacement Quality

Genuine Smith & Wesson factory parts manufactured to the exact specifications and tolerances of the originals — same dimensions, same cylinder timing geometry, same reliable lockup. No aftermarket substitutes.

Finding Your Model Number

Swing out the cylinder and check behind the yoke on the frame. Model numbers have been stamped there since 1957–58. If your revolver has no model number, it predates that era — contact us with the serial number and we'll help identify the correct part.

Questions? Call or email us — we're happy to help you get the right part the first time.